Box for use at high temperatures



Aug. 7, 1928.

E. P. VAN STONE BOX FOR USE AT HIGH TEMPERATURES Filed April '7, 1927 Patented Aug. 1928.

UNITED STATES YPWATENT oF icE.

EDWARD P. VAli' STONE, OI READING, IASSACHU'SliiElI'S, ASSIGNOB TO GENERAL ALLOYS COMPANY, OF BOSTON, KASSLOHUSETTfi, CORPORATION b1 MASSACHU- SETTS.

Application filed April 7,

This invention relates to boxes which are to be subjected alternately to a high temperature and then cooled such, for example, as carburizing boxes.

Heretofore boxes of this general type have been made with the side walls and bottom as an integral casting, the open end being provided generally with a depression into which a cover could be fitted. Boxes madein this manner had a relatively short life and soon developed cracks and warped due to the repeated-heating and cooling, giving a difier ential in expansion and contraction. Other attempts have been made to make such boxes with side plates secured by connected. cast corner pieces, but such boxes have been found practically impossible to manufacture owing to the differential iii expansion and contraction of the corner castin connections on cooling and have been short 'ved because.

of the strains imposed on the parts thereby.

It is an object of the present invention to provide a box of this general type which will better resist the operating conditions and strains encountered by alternate heating'and cooling, and which is constructed to resist the strains and shocks of handling better than those now in use. This is accomplished in part in accordance with the invention by providing a jacket open at opposite ends and, preferably, formed. of a pluralit of horizontally corrugated platesunite by mdependent corner castings. If desired, the

plates and the castings both may be corrugated and one or both of the open ends may be closed by a removable plate.

The invention will be more clearly understood from the following description inconjunction with the accompanying drawings; in which,

Fig. 1 is a plan view of a box the invention; and I Fig. 2 is a sectional view taken .uponthe line 2-2 of Fig. 1. j

In the drawings the invention is illustrated as an open ended body structure comprising a plurality of side plates 1 0 united at their juxtaposed edges by castings 11 of referably uniform cross section to form about the said edges, jackets or corner posts, the ends of which terminate substantially flush with the open ends of the body structure to provide a suitable continuous surface for engagement with closures such as 14.

It is an important feature of the invention embodying gnox FOB use A! man maxim-roams.

1927. serial no. 151,719.

that the said castings or corner postsare.

independent of each other, except in so far as they are connected by the said plateslO, so that they are freely movable relative to one another with the expansion or contraction of the said plates, and thereby do not impose such strain on the plates as would otherwise of the said plates to extend or contract in the direction of their length and subject to changing temperatures in their normalplane, instead of bending under the influence of such changing temperatures and thereby imposing strains at their junctures with the corner castings. Still furtherthe presence of the corrugations assists the plates in adapting themselves naturally to expansion and contraction of the corner castings in the direction of the length of the said castings. If desired, the connected end portions ofeach plate 10 maybe provided with an irregularity such as openings 1.2 to permit the entrance of the metal of castings 11 thereinto to form interlocking joints therewith. l

The closures 14 ofthebox are freely applied thereto so that they do not interfere with the expansion and contraction of'the plates 10 and the consequent movement of the castings 11 relative to one another so that the fpnction of the independent castings is suggested have a much longer life than those wherein the welding of side plates to the frame is resorted to, resultin in, what amounts to practically an air chi led casting at such welding points,-which includes those parts of the plate immediately adjacent the weld, and it is further found that they. do

notsulfer from the defects attending carburizing boxes in which the side plates are set in a frame wherein the corner posts are rigidly connected together as heretofore known.

The importance of increasing the life of such boxes will be readily appreciated in view of the fact that heat resisting metals or alloys, which it is necessary to use in the construction of such boxes, are expensive commodities, and where carburizing or similar operations are carried out, the expense of maintaining carburizing boxes is quite heavy.

This invention may be developed within the scope of the following claims without departing from the essential features of the saidinvention, and it is desired that the specification and drawings be read as being merely illustrative and not in a limiting necting said plates, said members being independent-of each other and freely movable with the expansion and contraction of said plates.

3. In a box for use at high temperatures, an open ended wall structure including a plurality of sheet metal side plates, and cast members connecting said plates, said cast members terminating substantially at the upper and lower edges of said plates and being independent of one another.

4. In a box for use at high temperatures, an open ended wall structure comprising a plurality of sheet metal side plates, cast members connecting said plates, said members being independent of each other, and closures for the ends of said wall structure, said plates and said cast members being freely movable over the opposed surface of said closures.

I 5. In a box for use at high temperatures, an open ended wall structure comprisin a plurality of sheet metal side plates provided with surface irregularities near their juxtaposededges, and cast members overlapping the said edges and interlocking with the said surface irregularities;

6. In a carburizing box, an open ended wall structure comprising a plurality of sheet metal side plates provided with surface irregularities near their juxtaposed edges, and cast members overlapping the said edges and interlocking with the said surface irregularities, said members being independent of each other and freely movable with the expansion and contraction of said plates.

In testimony whereof I afiix my signature.

EDWARD P. VAN STONE. 

